Method of forming a printhead

Abstract

A method of bonding two semiconductor substrates to form a printhead includes aligning a top surface of a first substrate with a second substrate, wherein the first substrate has a fluid channel in the top surface, heating the first and second substrates to a first temperature in a partial vacuum, and placing the top surface of the first substrate in contact with the second substrate to form a bond.

1. A method of bonding two semiconductor substrates to form a printhead comprising:
 providing a first substrate and a second substrate separate from the first substrate; 
 aligning a top surface of the first substrate with a bottom surface of the second substrate, wherein the first substrate has a fluid channel in the top surface; 
 heating the first and second substrates to a first temperature in a vacuum pressure; and 
 placing the top surface of the first substrate in contact with the bottom surface of the second substrate while heating the first and second substrates to the first temperature in the vacuum pressure to form a fusion bond between the top surface of the first substrate and the bottom surface of the second substrate, 
 wherein a patterned etch mask layer is formed on at least one of the top surface of the first substrate and the bottom surface of the second substrate, 
 wherein the patterned etch mask layer is formed on the top surface of the first substrate and has at least one opening defined therein, wherein the at least one opening is aligned with the fluid channel in the top surface of the first substrate. 
 
   
   
     2. The method of  claim 1  wherein the first substrate and the second substrate are formed of silicon, and the patterned etch mask layer is formed of oxide. 
   
   
     3. The method of  claim 1  wherein the bond is a silicon direct wafer bond. 
   
   
     4. The method of  claim 1  further comprising heating the bonded substrates to a second temperature to thermally anneal. 
   
   
     5. The method of  claim 1  wherein the bond is a silicon to silicon bond. 
   
   
     6. The method of  claim 1  wherein the bond is a silicon to silicon dioxide bond. 
   
   
     7. The method of  claim 1  wherein the bond is a silicon dioxide to silicon dioxide bond. 
   
   
     8. The method of  claim 1  wherein the bond is a silicon to silicon nitride bond. 
   
   
     9. A method of bonding two semiconductor substrates to form a print head comprising:
 providing a first substrate with top and bottom opposed planar surfaces with a patterned mask layer on the top planar surface, the patterned mask layer being formed of oxide; 
 providing a second substrate with top and bottom opposed planar surfaces, the second substrate being separate from the first substrate; 
 aligning the top planar surface of the first substrate with the bottom planar surface of the second substrate; 
 heating the first and second substrates to a first temperature in a vacuum pressure; and 
 placing the top planar surface of the first substrate in contact with the bottom planar surface of the second substrate while heating the first and second substrates to the first temperature in the vacuum pressure to form a fusion bond between the top planar surface of the first substrate and the bottom planar surface of the second substrate, 
 wherein the first substrate has a fluid channel in the top planar surface, and wherein an opening of the patterned mask layer is aligned with the fluid channel. 
 
   
   
     10. The method of  claim 9  wherein forming the bond between the top planar surface of the first substrate and the bottom planar surface of the second substrate includes interposing the patterned mask layer between the first substrate and the second substrate. 
   
   
     11. The method of  claim 9  wherein the first substrate and the second substrate are formed of silicon. 
   
   
     12. The method of  claim 9  wherein the bond is a silicon direct wafer bond. 
   
   
     13. The method of  claim 9  further comprising:
 heating the bonded substrates to a second temperature to thermally anneal them. 
 
   
   
     14. The method of  claim 9  wherein the bond is a silicon to silicon dioxide bond. 
   
   
     15. The method of  claim 9  wherein the bond is a silicon dioxide to silicon dioxide bond. 
   
   
     16. The method of  claim 9  wherein the bond is a silicon to silicon nitride bond. 
   
   
     17. The method of  claim 9  wherein the bond is a silicon to silicon bond.